Process of coating webs of paper with leaf metal.



B. BRANDT.

roonss oF coATING wBBs oF PAPER WITH LBAF METAL.

AYPLIOATION I'ILED JULY 15, 1913.

Patented May 19, 1914.

2 SHEETB-SHEBT 2.

UNITED STATES PATENT OFFICE.

EMIL BRANDT, OF MUN'ICH, GERMANY.

PROCESS OF COATING WEBS OF PAPER WITH LEAF METAL.

To all whom 'it may concern:

Be it known that I, EMIL BRANDT, citizen of Germany, residing at Munich,Bavaria, Germany, have invented certain new and useful Improvements inthe Process of Coating 'Webs of Paper with Leaf Metal; and I do herebydeclare the following to be a full, clear, and exact description of ltheinvention, such as will enable others skilled in the. art, to which itappertains to make and use the same. 4

One known method of coating a strip of paper with leaf metal consists inwinding the paper, with an adhesve substance thereon, together with astrip carrying thev leaf metal, the leaf being pressed between the twostrips by the tension applied in winding them. WVith this process it isonly possible to feed the metal'leaf from one roll, because if severalfeed rolls were placed side by side, in order to coat a wider strip orweb of paper, creases would be too liable to be formed in the course oftransferring the several strips of leaf metal to the strip of paper tobe coated. Moreover, as the leaf is gener-l ally subjected to the actionof a blower while being applied to the strip to be eoated, the

is liable to shift the strips at the sides thereof. The adhesive used'must be one which dries quickly, and one which is notI soluble inwater, as the eoated paper is used for cigarette ti s. This necessitatesthe use of resinous a hesives and the like, and with these the eoatedpaper cannot be given a high polish, because the adhesive is melted bythe heat produced by the operation of polishing.

In another known process, a web of cigarette paper receives pieces ofleaf metal at intervals from a traveling carrier, which takes a separatepath after applyiug the leaf metal, no regulation of pressure beingeffected or attempted. With this process, only portions of the surfaceof the paper are eoated with leaf metal, so that it is not in the fullsense a process of producing metal-` coated paper.

The object of the present invention is to enable wide and narrow webs ofpaper to be eoated over their entire surface with leaf metal which 'isapplied with regulatable pressure, and to which a high polish can begiven if desired. To this end the web to be eoated with leaf metal, anda traveling web carrying the leaf metal, are brought to- Speoificaton ofLetters Patent.

Application med July 15, 1913,

air current acting o-n one strip of leaf metal' Patented May 19, 1914.

serial No. 779,095.

gether under ressure, as for example between two ro lers, the pressurebeing removed after the transfer of the leaf to the firstmentioned web,and thel two webs then continuing their travel in separate paths. Theamount of pressure applicd may be regulated by regulating the periodduring which the two webs are subjected to the pressure. If the adhesiveused is one which dries slowly and is soluble in water, a high polishcan be applied to the eoated paper, because such adhesives do not becomesoft in the course of the polishing process. The leaf metal can be verytirmly attached, and the adhesive is not liable to penetrate throughsuch small holes as sometimes occur in leaf metal.

Provided that the eoated web is Separated from the carrier webimmediately after removal of the pressure, it will be clear that aplurality of leaf metal feed rolls may be used side by side, or onebehind the other, each having a separate pressure roll, the severalpressure rolls being arranged at the periphery of a larger roll for theweb to be eoated. Several strips of leaf metal can thus be placed sideby side on a web, slightly overlapping each other to obviate gaps.

The invention is illustrated in the accompanying drawing, in which.-

Figure l is a diagram' illustrating one method of carrying the processinto effect. Fg. 2 is a sectional diagram, illustrating an'- other modeof operation, and Fig. 3 is a similar view, illustrating a third mode ofoperation; Fig. 4 is a mutilated plan view of the leaf metal rolls andwebs shown in Fig. 3, and Fig. 5 is a section of the webs on the lineA--B of Fig. 4. Fig. 6 is a sectional diagram illustrating another modeof operation, Fig. 7 being a mutilated plan view of the leaf metal rollsand webs, Fig. 8 a section of the webs on the line C-D of Fig. 7, andFig. 9 a olan view of one of the webs.

Referring in the first instance to Fig. 1,

tothe roller c by suitable gearing, so that'as the two rollers arerotated the leaf metal is transferred to the web b at the place ofcontact. The web b thus coated may be fedV to a drying apparatus andthereuponl either wound onto a roller, cut into sheets or otherwisetreated, while the web e having transferred the leaf metal, is wound upon the roller b.

It will be apparent that'it is possible to regulate the period duringwhich those parts of the webs b and e, f, which are brought together,remain in contact with each other; this can be done by making themtravel together around a greater or less part of the circumference ofone of the rollers c, g, with regulatable pressure. Two or more rollsmay be arranged side by side, with a similar number of pressure rollersg provided adjacent the periphery of the roller c.

The adhesive is preferably applied to the Web b beforehand, the web thenbeing dried and rolled. The prepared web, with the dried adhesivethereon, is subsequently, before being coated with metal leaf, unrolledand passed through water, and then rolled up again while wet, so thatthe adhesive be-A comes active and is distributed in the form of an evenfilm by the pressure applied in rolling. The web itself becomesuniformly saturated with moisture from both sides, so that when usedafter a few hours it travels smoothly, without creasing, over the rollerc.

The above described mode of operation requires uniform saturation of theweb b with water, in order to obtain Smooth and uniform coating of leafmetal. The quantity of adhesive applied is so regulated that the coatedpaper has the requisite fiexibility when subsequently passing throughthe polishing machine.

In certain cases, for instance with thin or porous kinds of paper, the'adhesive alone will sutice to completely saturate the paper withmosture. The described saturating process may also be used indepcndentlyof the above described process of producing metal coated aper.

In the above described mode of operation the contact of the two webs isbrought about by and between two rollers.

As the leaf' metal is not in the form of a continuous strip but consistsof a number of leaves arranged one behind the other on the paperbacking, or carrier, it may occur that individual leaves become detachedfrom the backing'while passing over the roller, and may slide forwardand vbecome crumpled between the rollers, in which condition it is thenapplied to the paper strip to be coated, a portion of the latterremaining bare. In order to avoidthis contingency,

the lweb coated with the adhesive may be drawn with its coated sidefacing inward over a convexcurved surface, the web or webs carrying themetal leaf being causcd to travel between the said convex surface andthe adhesive web, so that theleaf metal is pressed by the stretched websagainst the ad esive surface. This arrangement not only obviates 'theabove mentioneddisad- Vantage but renders the use of toothed gearing andother transmission gear unnecessary. The movement of all the rollers andthe control of this movement are effected solely by the pull of the webof paper coated with the metal leaf. The convex surface is preferablyformed by a plurality 'of rollers arranged in' a curve, thisVarrangement being better than a single large roller, inasmuch as itprevents the occurrence of creases even when coating wide webs. Anarrangement working on this principle is shown diagrammatically in Fig.2, in which al designates the paper roll, and bl the web drawn therefromto be coated with leaf metal fl drawn from a roll dl together with acarrier web el of paper or the like. i is a fixed or rotating roller, onthe periphery k of which the web of paper bl is brou ht into contactwith the leaf metal. lis a ro ler of large diameter, which draws off thecoated web from the periphery le, and at the same time draws the webs bland el from their respective rolls. The roll al is preferably providedwithv a suitable brake device in order to keep the paper and leaf metalwebs at the proper tension when passing around the roller h is the rollon which the carrier webel is rewound.

The operation is as follows: The draw-ofi' roller Z is rotated and byadhesion moves the Vwet, adhesive web bl, pulling the said web off itsroll al. The web bl passing around the roller z' with its adhesive sidefacing the latter, meets at m the web el, with the leaf metal facingoutward, so that the leaf metal is transferred to the adhesive side ofthe web bl. The latter pulls the web el with the leaf metal fl off theroll all at the same` speed as that at which it travels itself. Whilethe webs are travelingover surface le intimate, smooth and uniformconnection of metal with paper -is effected. The blank web el leaves thecoated web at n and is wound on the roll k for subsequent use, and themetal coated web is dried by any known drying apparatus, androlled upfor further treatment' or use. The web el prevents the metal leaf whichit carries from being damaged by thel surface k and also enables verythin and wet paper to be coated, as it takes part of the tension.

The arrangement shown diagrammatically in Figs. 3, 4 and 5 issubstantially similar to that shown in Fig. 2, but in this case thereare two pairs of carrer webs el, el,

carrier webs (24, with are of the same width as drawn from rolls dz, da,with leaf metal fz, f3 thereon, the two rolls forming each pair lyingcoaxially side by side, and the rolls da* being set back, so that thewebs can bc made to overlap, as shown at o in Figs. 4 and 5. The carrierwebs with the leaf metal meet at m2 the adhesive paper web bz drawn fromthe roll az, and then travel under the web b2 over the surface 702 ofthe roller iz, and thence to the roller lz. At In,2 the carrier web searates from the coated paper web 62. On t e surface 7::2 of the rolleriz the edges p of the webs 62, lying upon the leaf metal f3 carried bythe webs es, cut away the overlapped parts o of this leaf, so that cleanjoints are made where the strips of leaf metal meet at the sides. Ofcourse the material forming the webs 62 must be thin but yet strong inorder that the edges of these webs are capable of performing thisCutting action.

In the arrangement shown in Figs. 6 to 9, the curved path k* for aplurality of fixed or rotatable rollers q arranged in an are. The web ofpaper b* to be coated with metal leaf travels from a roll a* to mi, andthen over the rollers g to a roller 14. There are two rolls cl*supplying metal leaf f4 thereon. There are also two rolls als supplyingcarrier webs 05 with metal leaf f5 thereon. The several carrier webstravel side by side, their edges practically meeting, and the strips ofmetal leaf f* are of the same width as the carriers et The strips ofmetal leaf f5 on the carrier 65 are, however, wider than the saidcarriers, so that these strips overlap the strips f4, as shown in Figs.7 and 8. lVhile wound on the rolls (ZE the strips f5 are covered byprotective strips 66, which the strips of leaf metal f5 and lie betweenthe latter and the carrier webs 65. In the course of unwinding, thestrips e, which serve only for protection during packing, transport,Storage etc., are wound up separately, as at h6 and leave the leaf metalexposed for transfer to the web 64. i

Above the roller l* there is pressure roll fr, weighted or acted on bySprings, so that it bears on the carrier webs. After passing betweenthis roll r and the roller l* the carthe webs is formed by rier webs e4,65 are wound up separately to form a roll hi, and the coated web b*continues its travel in another direction.

In all forms of the invention, suitable means, such as the take-uproller h illustrated in Figs. 1 and 2, is provided to wind up thecarrier web after the metal leaf has been transferred to the adhesiveweb. The carrier web, after removal of the metal leaf therefrom iscaused to travel in one direc-` tion by the roller h, while the adhesiveweb provided with the leaf is caused by manual or mechanical means totravel in a different direction, thus causing the carrier web toseparate from the coated web.

What I claim as my invention and desire to secure by Letters Patent ofthe United States is- 1'. The herein described process of applying metalleaf to a web, which process consists in simultaneously passin anadhesive web and a carrier having meta leaf thereon while in contactwith each other abouta platen surface, exertmg pressure against saidsurface through tensoning of said'carrier and said web whereby acontinuing surface pressure is exerted upon said web and said carrier'to insure application of said leaf to said web, and finally separatingsaid carrier and said lweb after pressure i thereon has ceased.

2. The herein described rocess of applying metal leaf to a web, w ichprocess consists in simultaneously passing an adhesive web and aplurality of carriers each provided with metal leaf thereon, while incontact with each` other about a platen surface, exerting pressureagainst saidl surface through tensioning of said carriers and said webwhereby aicontinuing surface pressure is exerted upon said web and saidcarriers to insure application of saidl metal leaf from all of saidcarriers to said web, and finally separating said carriers and said webafter such pressure has ceased. I

In testimony whereof I hereunto aflix my signature in the presence oftwo witnesses. EMIL BRANDT.

Witnesses:

A. V. W. Corrnn, RICHARD Lnmr.

